1. Field of the Invention
The present application relates to a frame for gliding sport articles such as roller skates, ice skates.
2. Description of Background and Relevant Information
The frames of the aforementioned type are adapted for the linkage between one or more gliding members themselves (namely the ice skate blade, wheels or rollers) and the user's foot between which it is inserted.
The frames are therefore generally constituted by a bearing surface capable of receiving the athlete's shoe, and by one or two longitudinal lateral flanges adapted to receive the wheels, rollers or the skate blade.
They must also have substantial mechanical resistance characteristics while being as light as possible in order not to require too substantial efforts from the athlete.
Furthermore, the advanced technology in these gliding sport articles, especially in the case of in-line roller skates, further increases the requirements, which must be met by the skate frames, and which must reach a compromise between:
an increased mechanical resistance and stability, especially for the speed skates, but also for the so-called "free ride", "free style" or "hockey" skates, in order to offer efficiency and an unquestionable response in the transmission of movements to the skate by the skater; PA1 a certain flexibility, especially in certain zones of the skate to allow for an adaptation of the shape of the skate to the path taken, especially on curves at high speeds, but also the dampening of shocks and vibrations, PA1 as light a weight as possible.
Furthermore, it is known that the front wheels are the first to receive the ground impacts, whereas the rear wheels transmit the most power.
Currently known techniques for making frames do not allow meeting all these requirements while maintaining a reasonable manufacturing cost.
Indeed, the oldest manufacturing technique consists of making such frames from folded sheet metal, in a U-shape, as shown in the German patent DE 10 33 569, for example.
Such a construction method, although inexpensive, does not, however, allow obtaining frames with great mechanical resistance except by substantially increasing the thickness of the sheet metal and therefore its weight, and it allows obtaining a certain flexibility in selected areas even less.
Another commonly used technique consists of making the frames entirely by molding from synthetic or even metallic materials. The integral molding offers the advantage of allowing sufficiently varied forms, but furthermore presents numerous disadvantages, the main disadvantage being the impossibility of the compromise sought and cited previously, for even if the constitutive material of the frame has characteristics of stiffness, it cannot offer at the same time characteristics of flexibility, except by providing zones that are more or less thick according to their function, but this would lead to molds having a burdensome design because it is complicated.
In this field, frames made from composite fibers are also known. Such frames can actually be made in almost any shape possible, but their construction is extremely expensive and hard to industrialize. Moreover, such frames are certainly very stiff but lack flexibility and are therefore fragile and uncomfortable.
Finally, U.S. Pat. No. 5,388,846 proposed making a frame for an ice skate or a roller skate from a sectioned metallic bar whose transverse section corresponds to the general section desired for the frame, the final shape of the frame being obtained after machining with removal of material.
Such a construction method is again very expensive, given the machining time necessary and the quantity of material that must be removed. In addition, it does not allow great freedom with respect to the shape or profile of the frame, nor in seeking the mentioned compromise.
U.S. Pat. No. 3,086,787 from C. A. Wyche relates to a roller skate with an adjustable length whose stability and stiffness are ensured regardless of the number of rollers and the distance separating the front and rear rollers. The skate comprises a support plate bent in an inverted U-shape, preferably made of fairly thin steel on which elements are slidably mounted for maintaining the heel and tip of the foot. To each of the side portions of the support plate, there is welded or screwed a downwardly extending metal plate, preferably made of hardened steel and extending the full length of the skate.